Means for cooling gas-engines.



G. C. JONES.

MEANS FOR COOLING GAS ENGINES.

APPLICATION FILED MAB. 5, 1909.

1 02,359 Patented June 4, 1912.

CHESTER CHARLES JONES, OF BEATRICE, NEBRASKA.

MEANS FOR COOLING- GAS-ENGINES.

Specification of Letters Patent.

Patented June 4, 11.9112.

Application filed March 5, 1909. Serial No. 481,274.

To all whom it-may concern:

Be' it known that I, CHESTER CHARLES J ONES, a citizen of the United States, residing at Beatrice, in the county of Gage and State of Nebraska, have invented a new and useful Means for Cooling Gas-Engines, of which the following is a specification.

This invention has reference to improvements in means for cooling gas engines and is designed to provide heat radiating means especially for that portion of the explosion chamber including the piston head. Since it is desirable to avoid the use of water jackets, the exterior walls of the cylinder for adistance about coincident with the length of the explosion chamber, can a large number of heat radiating fins ma e'of some good heat conducting material such, for instance,

as copper, to present a very large radiating surface to the action of the atmosphere.

While heat radiating fins for explosion chambers of explosion engines have been in common use for a long time, such fins are usually cast in one piece with the walls of the engine cylinder. Furthermore difficulty is found in air cooled engines with the high temperature developed in the interior of the piston the head of which latter constitutes the front or forward wall of the explosion chamber and is therefore subjected to the heating effect of the hot gases of combustion. When an explosive mixture is introduced into the crank case and from there directed to the explosion chamber, undue heating of the piston, besides being detrimental to good lubrication may cause a premature explosion of the charge while still in the crankcase and thereby seriously injure or destroy the engine. In two-cycle engines it is the custom to introduce either the explosive mixture already formed through the crank case or to introduce air only through the crank case, in either instance the contents of the crank case being under considerable pressure before the passage leading to the explosion chamber isopened. In accordance with the present invention that face of the head of the piston remote from the explosion chamber is provided with 0 means whereby the radiating vsurface is greatl augmented, and means are provided where y the compressed contents of the crank chamber must traverse these radiating surfaces before reaching the port through which the compressed contents escape to the explosion chamber. Even though the compression to which the air or gaseous charge in the crank case is subjected tends to heat the same to a small extent, the temperature of the contents of the crank case is far below that of the contents of the explosion chamber after an explosion and consequently the movement of the contents of the crank case past the radiating surface on the forward face of the piston head tends to absorb any heat which may have traversed the piston head from the explosion chamber and so maintain the piston head in a workably cool condition, while the heating of the contents of the crank case due to the absorption of the heat transmitted from theexplosion'chamber to the piston head is advantageous in facilitating the ignition of the charge after being compressed within the explosion chamber.

The invention will be best understood from a consideration of the following detail description taken in connection with the accompanying drawings forming a part of this specification, in which drawings,

Figure l.is a longitudinal central section through an explosion engine of the two-cycle type constructed in accordance with the present invention. Fig. 2 is a perspective view of a few of the radiating fins that are applied to the exterior of the engine cylinder.

Referring to the drawings there is shown an engine cylinder 1 which may be taken as typical of any of the many makes of engines, and this cylinder has interior thereto apiston 2 of the ordinary trunk type so far as its general structure is concerned but modified in certain respects which will hereinafter be referred to.

The engine is shown as a two-cycle engine and is therefore provided with a crank case 3. In the particular structure shown the engine is shown as an upright engine and the crank case is provided with wings or extensions t designed to uphold the engine by being attached to any suitable support whether,

the same be the running gear of the vehicle or a supporting framework in a boat or a suitable base where the engine is designed to remain fixed in space when in operation.

Produced in the outer wall of the cylinder 1 along the zone of the explosion chamber 5 is a continuous helical groove or a series of parallel grooves 6. This groove or these grooves are designed to receive radiating fins of any suitable material. While these fins may be made of any suitable material some good heat conducting material such as copper or brass is to be preferred although of course the invention is by no means limited to the use of such material. In order to 5 readily secure the fins in place and at the same time present a large radiatin surface these fins are made U-shaped as indicated in Figs. 1 and 2 and may be comparatively narrow in the direction of the circumference of the cylinder 1 as indicated in Fig. 2 although this does not preclude the making of these fins as wide as desired and the longitudinal splitting thereof to cause them to readily conform to the circumference of the cylinder 1. The fins 7 are held to the cylinder by wire fastening strands 8, which in the case of a continuous-helical groove about the cylinder will comprise a single wire strand of sufficient length to anchor-all the fins 7 to the cylinder.

When an explosion or a series of explosions takes place within the explosion chamber 5 the heat so generated is conducted through the walls of the cylinder 1 and if the radiation from the outer surface of the walls of the cylinder was alone depended upon to kee the cylinder cool it would befound that t e accumulation of heat was far in excess of the power of radiation and the engine cylinder would soon become red hot to the injury or destruction of the engine. When radiating fins are cast on the cylinder the heat generated by the explosion within the explosion chamber is radiated to such an extent as to keep the engine cylinder comparatively cool but still very much hotter than is the case with a water jacket.

By means of the U-shaped fins of the present invention a very large radiating surface is provided within a comparatively small compass and since the fins may be made of sheet metal and then bent into shape there is obtained a radiating surface far in excess of fins cast directly on the engine cylinder or fins made of sheet metal and cast into the engine cylinder.

In the draw)ings the usual exhaust port 9 is shown and opposite the same is shown the inlet. port for the scavengering charge of air or for the introduction of an explosive mixture drawn into and com ressed in the crank case 3, depending upon t e particular make of engine to which the invention may be applied. This port 10 is in communication through a passage 11 with a port 12 opening through the walls of the cylinder within range of the travel of the piston 2 which is usual in two cycle engines. A5 is further customary in two-cycle engines, the active face of the head of the piston is provided with a deflector 14 which, when brought into operative relation to the port 10 serves to dlrect the incoming com ressed charge of air toward the rear ,wall 0 the cylinder -1. In the showing of the drawings the head of the cylinder is curved toward the explosion chamber until it meets the deflector 14 and while this construction has certain advantages it is not material to the present invention and the head of the cylinder may be made inany other shape desired. Traversing the-piston 2 at a point about opposite the port 13 is a wrist pin 15 receiving the corprovided with-a matching port 13, all as is respondin end of a pitman 16 the other end of which is connected to a crank 17 within the crank case 3 in the usual manner.

Within. the piston 2 and extending from the inner face of the wall of the piston to ward th wrist pin 15 is a deflector plate 18 having i inner end close to the corresponding end f the pitman 16 which at this point is forms into a cylindrical bearing head or sleeve 19 so that even though the pitman oscillates about the wrist pin 15 the outer wall of the head 19 remains in substantially constant relation to the inner end of the web 18. I

Formed on the face of the piston head remote from the explosion chamber 5 are a number of elongated studs 20 which may be more or less conical in cross section with their faces closely adjacent and their apices more widely separated because of the conical shape of the studs. These studs are shown as formed in one piece with the head of the piston, this being the preferable though not necessarily the only manner of producing the studs, the purpose of which 1s to provide a large radiating surface on this face of the piston head, this surface being a nufnber of times greater than the area of the piston head due to its general shape. The air or other inlet port into the ,crank case due to such. movement of the piston there will be an inrush of air or explosive mixture through the port 21 into the crank case. On the explosion taking place in the explosion chamber, it being understood that a suitableigniter is assumed to have been introduced through the treaded opening 22 shown at the upper or outer end of the cylinder 1, the piston moves forward under the impulse of the explosion and immediately closes the port 21. On the forward movement of the piston 2 the air or Ill charge within the crank chamber 3 is compressed and this compression increases until the port 13 matches the port 12 and the rear end of the piston has uncovered the port 10, the burned gases having in the meantime discharged through the exhaust port 9. The operations just described are of course incident to an ordinary two-cycle explosion engine. On the opening of the ports 12 and 10 with the reduction of pressure in the explosion chamber because of the exhaust through the port 9 the compressed air or gases within the crank case 3 pass through the port 13 and port 12 into the passage 11 and then into the explosion chamber 5 through the port 10, but the route through which these gases must pass from the crank chamber into the interior of the piston and so to the passage 11 through the port 13 is determined by the presence of the web 18 which is directly adjacent to the port 13 on the crank side thereof while a free passage for the compressed air or gases is provided on the other side of the head 19 of the pitman 16 and therefore the stream of air or gases will pass around the head 19 and close to the piston head and the projecting studs, 20 before entering the passage-11 through the ports 12 and 13. The out-rushing stream of air or gases thus impinges directly against the studs 20 and as these studs become heated by conduction from the head of the piston they are quickly chilled or cooled by the action ofthe comparatively cool air or gases in the crank chamber. There is therefore a chilling of the piston head after each explosion taking place in the explosion chamber 5 and since the surface subjected to the chilling action of the cool stream of air or gases passing from the crank chamber through the interior of the piston and thence to the explosion chamber is largely due to the extensive area of the studs 20, the piston can never reach a dangerous temperature even though subjected to the very high temperatures developed in the explosion ehamchamber, other means may be utilized for providing the inner face of the piston head,

that is the face remote from the explosion chamber with a large radiating surface.

Since the two general types of cooling explosion engines are designed as Water-jacketed and air cooled even though oil or other liquid be used in place of water or other gas in place of air, the term air-cooled will be understood in this case as covering a gaseous cooling agent whether the same be actually air or a gaseous explosive mixture, the cooling action in either case being the same.

What is claimed is An air. cooled explosion engine including a hollow piston closed at one end, heat radiating studs extending from the inner or inactive face of the closed end of the piston, a wrist pin disposed diametrically within the piston, a pitman having a rounded head engaging the wrist pin, a deflector extending from the wall of the piston to one side of and close to the pitman head, said deflector and pitman head cooperating to deflect the gases toward one side portion of the piston and against the lugs, there being an outlet port for the gases within the piston close to and above the deflector.

In testimony that I claim the foregoing as my own, I have hereto aflixed my signature in the presence of two Witnesses.

CHESTER CHARLES JONES. 

